[crankshaft] Always force number representation for increment.

test/mjsunit/regress/regress-664087.js

Index: test/mjsunit/regress/regress-664087.js
diff --git a/test/mjsunit/regress/regress-664087.js b/test/mjsunit/regress/regress-664087.js
new file mode 100644
index 0000000000000000000000000000000000000000..67391679303fe8156053a177acc04115eef3e599
--- /dev/null
+++ b/test/mjsunit/regress/regress-664087.js
@@ -0,0 +1,21 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+function g() {
+  throw 1;
+}
+
+var v = { valueOf : g };
+
+function foo(v) {
+  v++;
+}
+
+%NeverOptimizeFunction(g);
+assertThrows(function () { foo(v); });
+assertThrows(function () { foo(v); });
+%OptimizeFunctionOnNextCall(foo);
+assertThrows(function () { foo(v); });